Longitudinal Medicare claims files contain information on the majority of particular acute-care medical services used by the elderly, and thus represent a valuable supplement to longitudinal surveys. Because of the complexities of the Medicare files and confidentiality issues, however, Medicare claims data have not been widely used by researchers. This project proposes to produce a CD-ROM containing a public-use version of all Medicare claims information for the AHEAD. The CD-ROM will include "summary" data for use by researchers whose primary interests are not health or utilization of medical care, and "detailed" data suitable for use by investigators with extensive interests in health and medical care. Based on methods developed by project consultants and consultations with AHEAD staff and users, these variables will maximize detail while preserving confidentiality. The CD-ROM will include software for accessing combinations of variables, a textual description of the variables, and information on their construction. Phase I will finalize the "detailed" and "summary" data elements from the Medicare files, test data element creation on at least a portion of the Medicare data for AHEAD respondents, develop draft documentation for the datasets, and determine the structure of the data product. PROPOSED COMMERCIAL APPLICATION: Targeted to researchers in both the academic and nonacademic communities, this project will create "detailed" and "summary" versions of public-use data incorporating all Medicare claims information for linkage to surveys of the elderly. The principal product will be a user-friendly CD-ROM for use with the Survey of Asset and Health Dynamics of the Oldest Old (AHEAD); analogous products could be developed for other longitudinal surveys.